Car-stopping apparatus



INVENTOR a (6 3W) 5 Sheets-Sheet '1 A. E EVANS ET AL CAR STOPPINGAPPARATUS Filed Feb. ll, 1930 April 21, 1931.

J $2 w Y L A ril 21, 1931. A. E. EVA-NS ET AL CAR STOPPING APPARATUSFiled Feb. 11. 1930 5 Sheets-Sheet 2 April 21, 1931.

CAR STOPPING APPARATUS 5 Sheets-Sheet 3 Filed Feb. 11. 1930 INVENTOR6April 21, 1931. EVANS ETAL 1,802,109

CAR STOPPING APPARATUS Filed Feb. 11, 1930 5 Sheets-Sheet 4 law windINVENTORE) April 21, 1931. A. E. EVANS ET AL CAR STOPPING APPARATUSFiled Feb. 11. 1930 5 Sheets-Sheet 5 2% it I INVENTOR5 Patented Apr. 21,1931 UNITED STATES PATENT OFFICE ALBERT E. EVANS, OF PITTSBURGH, ANDGUSTAVUS I. NAMECHE, OF FORD CITY, PE-1\Tl l'..

SYLVANIA, ASSIGNORS TO PITTSBURGH PLATE GLASS COLIPANY, A CORPORATION OFPENNSYLVANIA oAa-s'rorrine APPARATUS Application filed February 11,1930; Serial No. 427,547.

The invention relates to car stopping apparatus for use on the returntrack of a plate glass surfacing system. In a system of this kind, theglass to be surfaced is secured to the tops oi cars or tables, whichform a train and are moved on the work track slowly beneath a series ofgrinding and polishing runners. The cars are then returned to startingposition on a return track which parallels the wor: track, this beingaccomplished by an endless cable or drag chain, which is provided withdogs.

which engage the racks on the bottoms of the cars. During the period ofreturn, each' car must be stopped whilethe workmen remove the sheet ofpolished glass held in po sition on the bed of the car by means ofplaster. This requires several minutes during which time it is necessaryfor the workmen to stand between the car tracks as well as at the sides.The purpose of the present invention is to provide improved means tostop the cars for the glass removing or stripping operation, whichincludes means "for releasing the dogs bywhich the cars are secured tothe drag chain and means for braking the cars. A further object is toprovide means of the character specified which is automatic orsemi-automaticin operation and so arranged as to afford protection forthe workmen, and eliminate the possibility of any of them being caughtbetween the car which is being stripped of its glass, and the next carof the series which is being moved along by the drag chain. Certainembodiments of the invention are illustrated in the accompanyingdrawings, wherein:

Figure 1 is a plan view showing the gen eral arrangement of theapparatus. Fig. 2

and polishing machines, this being a means well known in the art foraccomplishing'this purpose. Extending longitudinally of the work Whenthe cars are track 1 is an endless drag chain for giving 7, thecarstheir'movement along the track,

such drag chain passing around a pair of sprockets at the ends of thetrack, a suitable means being provided for driving one of the sprockets.The drag chain constitutesthe means for moving the cars along the trackand to this end is provided with a series of spaced dogs 6,6, 6, etc.adaptedto engage the rack oars 4 and move the cars along the track.These dogs are preferably constructed as indicated in Fig. 4; with anend? adapted to fit between the teeth oi? the rack. The dogs are pivotedupon the pintlesS oi the drag chain and eachhave an end 9 which isheavier than the end 7, so that normally the end '7 is held in positionto engage theteeth of the rack 4;. 'VVhen the dog is in this positiontherefore, the car l is moved along its track at a relatively low rateof speed.

As heretofore pointed out, it is necessary to stop the cars successivelyfor limited periods in order to remove the glass sheet carried thereby,and in order to thus stop the car, the dog 6 must be moved to therelease position shown in Fig. l. This is accomplished by means of a cam10 having its ends turned down, as indicated in Figs. 2 and l, normallyheld in the position indicated in these figures. The cam is prefer ablyformed of two angles placed backto back, as indicated in Figs. 5 and 6,and supported by a series of arms-11, 12, 13, 14 and 15 pivoted at theirupper ends to the cam and carried at their lower ends on pivots 16, 16,16. 16 and to the shaft 17. and the shaft 17 are carried in suitableframe members, such as 18, 18 and 19, 19 shown in Figs. 6 and 7, suchmembers being suitably anchored to the foundation 20 by means of thebolts 21, 22, etc. The shaft 17 which carries the arm 13 is supported insuitable bearings 23, 23 (Fig. 7) and is extended laterally and providedwith a squared end 2-1. for the application of a wrench or othersuitable tool whereby the lever 13 may be rocked so as to raise andlower the cam 10. Power means are also provided for rocking the lever 17to raise and lower the cam in the form of the air cylinder provided witha suitable plunger and piston rod 26, the end of which is pivoted at 27to the lower end of the lever 13. When the cam 10 is in the position ofFig. 2, and the table 2 is carried over the cam by the drag chain 5, thecam engages the end of the dog 6 and swings it to unlocked position, asindicated in Figs. 2 and 4, thus releasing the table from the motivepower tending to carry it forward. hen it is desired to again couple upthe table to the drag chain, the cam is swung forward by admitting airto the air cylinder 25, which causes the upper end of the lever .13 toswing forward. The cam is in this manner lowered and any dog 6 whichhappens to be beneath. the table 2 swings to operative position, so thatits end 7 engages the rack +1, thus coupling the table to the dragchain.

In order to overcome the inertia of the table and cause it to stopwithin a short distance after the dog 6 has been released, suitablebraking means are provided along the line of movement of the :arsadjacent the cam .10 which releases the dog. This means comprises a pairof opposing brake shoes 28, 28 located on opposite sides of the cam andspring pressed inward so that they frequently engage surfaces on thelower side of the car body. The :-:urfa 'e:-; which the brake shoesengage are preferably the sides of the rack bars 4, the shoes beingshown in engagement with such rack bars in Fig. 6. The shoes arepreferably Tshape in cross section and are provided with wear plates 29,29. The shoes are mounted for moven'ient toward and from each other uponcrank arms 30, 30 and 30, 30 carried upon the vertical shafts 31, 31,and 32, 02s journalled in the frame members 18. The lower ends of theshafts 31, 31 and 32, 82 are provided with crank arms 33, 33 and 38, 33connected to the rods 34, 34; and 3t, 3 1- The rods are mounted slidablyat their outer ends in sleeves Fig. 6) and adjusting nuts 36 arethreaded to these sleeves inside the brackets 37 through which thesleeves extend. A washer 38 is carried adjacent the The pivots 16 innerend of each of the rods 34, and be tween such washer and the sleeve 35 aspring 39 is positioned. By adjusting the sleeves 35, the springs 39 areplaced under any desired degree of compression and this presses theshoes 28 inward so that when they engage the rack bars 4-, the cars willbe stopped as soon as may be desired. "he degree of compression which isrequired in the springs 39 is easily determined by trial. The sleevesare adjusted by means of the rods 40 which have their inner ends squaredand fitting into the sleeves 35 and also have their outer ends squaredfor the reception of a wrench or other suitable adjusting tool.

After the table has been stripped of the glass plate carried thereby andit is desired that the table should continue its forward movement, thebrake shoes must, of course, be released and this is accon'iplished bythe actuation of the means which lowers the cam 10 in order to permitone of the dogs 6 to swing by gravity so that it will engage the rackbar 4. as heretofore described. The movement of the brake shoes todisengage them from the sides of the rack bar is accomplished by meansof the pairs of toggle links i1, i1 and 41, 41 (Fig. 3) which areconnected at their outer ends to the pairs of' lever arms 42, -12secured to the lower ends of the vertical shafts 31, 31 and 32, 32. Theinner ends of the toggle links 11, 1:1 and 4:1, 41 are pivotallyconnected to a release member comprising the two end brackets d3, 43connected together by the link M. The right hand. bracket (Figs. 3 and4) is connected by means of the link it with the lever 13, which leverserves to move the cam member 10 up and down, as heretofore explained.It follows that when the lever 13 is rocked around the shaft 17 to lowerthe cam, the links 11, 1-1 and -11, 41 are moved inward, thus rotatingthe shafts 33', 31 and 32, 32, so that the arms 33, 33 and 33, 33 areswung outward, thus releasing the brake shoes. At the same time thedownward movement of the cam member 10 permits the dog (3 lying beneaththe rack 4: to engage such rack so that the forward movement of the dragchain carries the table ahead.

As shown in Figs. 1 and 2, two sets of cams and brake shoes are providedso that the two tables 2 and 3 are stopped in the position shown. Thecam and braking devices for stopping the car 3 are precisely the same asthose for stopping the car 2 heretofore described and the purpose ofproviding the second set of aims and brake shoes for stopping the car 3is to protect the workmen who are engaged in removing the glass from thetable 2. The table 3 will always be stopped in the position shown,preferably about six feet from the table 2, although this may bemodified to meet varying conditions. After the glass has been removedfrom the table 2, as heretofore described, the cam and braking devicesare released by admitting air to the cylinder 25, and after this hasbeen done, one of the operators similarly releases the table 3 byoperating the valve which admits air to the cylinder 25a. lhe two tablesare then moved forward by the drag chain and when the table 3 reachesthe position formerly occupied by the table 2, it is automaticallystopped as heretofore described, while a third table which isapproaching from the right takes the place of the table 3 beingautomatically stopped in the position formerly occupied by the table 3.If desired, the cam and brake-releasing devices may be operated by handby applying a tool to the shaft 17 (Fig. 7), as heretofore described,although the amount of force required to move the parts is veryconsiderable so that the cylinder 25 is ordinarily used.

Fig. 8 illustrates a modification showing how the operation of theapparatus may be made entirely automatic, thus dispensing with therequirement by the workmen to operate the valves of the cylinder 25 orthe shaft 17. In this construction, the means for supporting andoperating the cams l0 and the brake shoes is substantially the same asthat described in connection with Figs. 1 to 7, but instead of havingthe lever '13 operated from the air cylinder, this lever 13 is operatedby a lever 45 connected to the lever 13 by a link as. The lever 45 isprovided at its upper end with a roller which lies in the path ofmovement of the table 47 which is following the table 48. ,A similararrangement is provided immediate the table 48 and the table 47 whichprecedes it. The forward movement of the table L7 serves to release thetable 48, and as soon as this table is released, it moves forward andcauses the release of the table 4 7, the latter table being the one uponwhich the workmen operate to remove the glass. EBy this arrangement thetables are kept spaced apart a uniform distance and the workmen arerelieved of the labor incident to the starting and stopping of thetables.

\Vhat we claim is:

1. In combination with a return track, a seriesof cars thereon, and adriven endless drag member beneath the cars, releasable dogs on the dragmember at spaced intervals'normally engaging the cars for moving themalong the track, and a movable cam located along the path of movement ofthe dogs and adapted, when in one position,'to engage the dogs and movethem to release position, and when in another position, to "be free ofoperative engagement with the dogs.

2. In combination with a return track, a series of cars thereon, and adriven endless drag-member beneath the cars, releasable dogs on the dragmember at spaced intervals normally engaging the cars for moving themalong the track, and a pair of movable cams located at spaced intervalsalong the path of movement of the dogs and each adapted, when in oneposition, to engage the dogs and move them to release position,and whenin another position, to be free of operative engagement with the dogs.

3. In combination with a return track, a'

series of cars thereon, and a driven endless drag member beneath thecars, releasable dogs on the drag member at spaced intervals normallyengaging the cars for moving them along the track, a movable cam locatedalong the path of movement of the. dogs, and adapted, when in oneposition, to engage the dogs and move them to release position, and whenin another position, to be free of operative engagement with thedogs,=,braking means for the cars which become effective to check themovement of the cars when the dogs are released, and means formoving thecam to position to release the dogs and also moving the braking means torelease position.

4. In combination with a return track, a series of cars thereon, and adriven endless drag member beneath the cars, releasable dogs on the dragmember at spaced intervals normally engaging the cars for moving themalong the track, a movable cam located along the path of movement of thedogs, and adapted, when in one position, to engage the dogs and movethem to release position, and when in another position, to be free ofoperative engagement with the dogs, braking means for the cars locatedalong the path of movement of the c; adjacent said cam and yieldinglyheld in position to engage a car and check its forward movement when thedog-which moves the car is released by the cam, and a common means formoving the cam to position to release said dog and also moving thebraking means to release position.

5. In combination with a return track, a series of cars thereon, and adriven endless drag member beneath the cars, releasable dogs on the dragmember at spaced intervals normally engaging the cars for moving.

them along the track, a pair of movable cams located at spaced intervalsalong the path of movement of the dogs, and each adapted,when in oneposition, to engage the dogs and move'them to release position, and wheninanot-her position, to be free of operative engagement with the dogs, abraking means located along the'path of movement of the cars adjacenteach of said cams and each yieldingly held in position to engage a carand check its forward movement when the dog which moves the car isreleased by its cam and a common means for moving each cam and thebraking means adjacent thereto.

(5. In combination with a return track, a series of cars thereon, and adriven endless drag member beneath the cars, releasable dogs on the dragmember at spaced intervals normally engaging the cars for moving themalong the track, a movable cam located along the path of movement of thedogs, and adapted, when in one position, to engage the dogs and movethem to release position, and when in another position, to be free ofoperative engagement with the dogs, a brake shoe extending along thepath of movement of the cars adjacent the cam, means for normallypressing the shoe yieldingly toward a part of the car so that it willfrictionally engage such. part as the car moves past the shoe, andoperating means connected to the cam and to the shoe so that when movedin one direction it will move the cam from its dog engaging position andwill also move the brake shoe to release position.

7. In combination with a return track, a series of cars thereon, and adriven endless drag member beneath the cars, releasable dogs on the dragmember at spaced intervals normally engaging the cars for moving themalong the track, a movable cam located along the path of movement of thedogs, and adapted, when in one position, to engage the dogs and movethem to release position, and when in another position, to be free ofoperative engagement with the dogs, a pair of opposing brake shoesextending along the path of movement of the cars adjacent the cam, meansfor normally pressing the shoes yieldingly toward each other and againstthe sides of a part of the car lying therebetween, so that they willfrictionally engage such part as the car moves past the shoes, andoperating means connected to the cam and to the shoes so that when movedin one direction it will move the cam from its dog engaging position andwill also move the brake shoes apart to release position.

8. In combination with a return track, a series of cars thereon, eachhaving a downwardly facing rack extending longitudinally of the car bodyon its lower side, and a driven endless drag member beneath the cars,releasable dogs on the drag member at spaced intervals having engagingparts which normally engage the racks on the cars when such racks lieover the dogs, and a vertically movable cam located beneath the path ofmovement of the drag member, and adapted, when in one position, toengage the dogs and move them to position of disengagement with respectto the racks, and when in another position, to be free of engagementwith the dogs so that such dogs will engage the racks.

In testimony whereof, we have hereunto subscribed our names.

ALBERT E, EVANS. GUSTAVUS J. NAMECHE.

